ARM: dts: am3874-iceboard: Fix 'i2c-mux-idle-disconnect' usage
diff mbox series

Message ID 20191004014548.29583-1-andrew.smirnov@gmail.com
State New
Headers show
Series
  • ARM: dts: am3874-iceboard: Fix 'i2c-mux-idle-disconnect' usage
Related show

Commit Message

Andrey Smirnov Oct. 4, 2019, 1:45 a.m. UTC
According to
Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt,
i2c-mux-idle-disconnect is a property of a parent node since it
pertains to the mux/switch as a whole, so move it there and drop all
of the concurrences in child nodes.

Fixes: d031773169df ("ARM: dts: Adds device tree file for McGill's IceBoard, based on TI AM3874")
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Benoît Cousson <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Graeme Smecher <gsmecher@threespeedlogic.com>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---

This is purely a drive-by fix, since it concerns the HW I've never
heard of before. However I was working with PCA9548
(vf610-zii-scu4-aib is my HW) and looking at various users in the
kernel, when this code caught my eye. Apologies for the noise if this
fix is somehow bogus.

In case that it matters this patch is based on top of 5.4-rc1.

Thanks,
Andrey Smirnov

 arch/arm/boot/dts/am3874-iceboard.dts | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

Comments

Graeme Smecher Oct. 4, 2019, 11:52 p.m. UTC | #1
Hi Andrey,

On 2019-10-03 6:45 p.m., Andrey Smirnov wrote:
> According to
> Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt,
> i2c-mux-idle-disconnect is a property of a parent node since it
> pertains to the mux/switch as a whole, so move it there and drop all
> of the concurrences in child nodes.
> 
> Fixes: d031773169df ("ARM: dts: Adds device tree file for McGill's IceBoard, based on TI AM3874")
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> Cc: Benoît Cousson <bcousson@baylibre.com>
> Cc: Tony Lindgren <tony@atomide.com>
> Cc: Graeme Smecher <gsmecher@threespeedlogic.com>
> Cc: linux-omap@vger.kernel.org
> Cc: devicetree@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
> 
> This is purely a drive-by fix, since it concerns the HW I've never
> heard of before. However I was working with PCA9548
> (vf610-zii-scu4-aib is my HW) and looking at various users in the
> kernel, when this code caught my eye. Apologies for the noise if this
> fix is somehow bogus.
> 
> In case that it matters this patch is based on top of 5.4-rc1.

Thanks! We do have I2C address collisions on downstream bus segments, so
keeping these segments isolated is important. I'm surprised this patch
was necessary and happy to see it.

Lightly tested on 5.3.

Tested-by: Graeme Smecher <gsmecher@threespeedlogic.com>

cheers,
Graeme
Tony Lindgren Oct. 8, 2019, 2:16 p.m. UTC | #2
* Graeme Smecher <gsmecher@threespeedlogic.com> [191004 23:53]:
> Hi Andrey,
> 
> On 2019-10-03 6:45 p.m., Andrey Smirnov wrote:
> > According to
> > Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt,
> > i2c-mux-idle-disconnect is a property of a parent node since it
> > pertains to the mux/switch as a whole, so move it there and drop all
> > of the concurrences in child nodes.
> > 
> > Fixes: d031773169df ("ARM: dts: Adds device tree file for McGill's IceBoard, based on TI AM3874")
> > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > Cc: Benoît Cousson <bcousson@baylibre.com>
> > Cc: Tony Lindgren <tony@atomide.com>
> > Cc: Graeme Smecher <gsmecher@threespeedlogic.com>
> > Cc: linux-omap@vger.kernel.org
> > Cc: devicetree@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> > ---
> > 
> > This is purely a drive-by fix, since it concerns the HW I've never
> > heard of before. However I was working with PCA9548
> > (vf610-zii-scu4-aib is my HW) and looking at various users in the
> > kernel, when this code caught my eye. Apologies for the noise if this
> > fix is somehow bogus.
> > 
> > In case that it matters this patch is based on top of 5.4-rc1.
> 
> Thanks! We do have I2C address collisions on downstream bus segments, so
> keeping these segments isolated is important. I'm surprised this patch
> was necessary and happy to see it.
> 
> Lightly tested on 5.3.
> 
> Tested-by: Graeme Smecher <gsmecher@threespeedlogic.com>

Applying into fixes thanks.

Tony

Patch
diff mbox series

diff --git a/arch/arm/boot/dts/am3874-iceboard.dts b/arch/arm/boot/dts/am3874-iceboard.dts
index 883fb85135d4..1b4b2b0500e4 100644
--- a/arch/arm/boot/dts/am3874-iceboard.dts
+++ b/arch/arm/boot/dts/am3874-iceboard.dts
@@ -111,13 +111,13 @@ 
 		reg = <0x70>;
 		#address-cells = <1>;
 		#size-cells = <0>;
+		i2c-mux-idle-disconnect;
 
 		i2c@0 {
 			/* FMC A */
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <0>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@1 {
@@ -125,7 +125,6 @@ 
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <1>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@2 {
@@ -133,7 +132,6 @@ 
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <2>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@3 {
@@ -141,7 +139,6 @@ 
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <3>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@4 {
@@ -149,14 +146,12 @@ 
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <4>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@5 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <5>;
-			i2c-mux-idle-disconnect;
 
 			ina230@40 { compatible = "ti,ina230"; reg = <0x40>; shunt-resistor = <5000>; };
 			ina230@41 { compatible = "ti,ina230"; reg = <0x41>; shunt-resistor = <5000>; };
@@ -182,14 +177,12 @@ 
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <6>;
-			i2c-mux-idle-disconnect;
 		};
 
 		i2c@7 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <7>;
-			i2c-mux-idle-disconnect;
 
 			u41: pca9575@20 {
 				compatible = "nxp,pca9575";